Correlation Between the Lauge-Hansen Classification and Ligament Injuries in Ankle Fractures.

OBJECTIVE:
To evaluate the ability of the Lauge-Hansen classification to predict ligament injuries in ankle fractures using magnetic resonance imaging (MRI) and intraoperative findings.

DESIGN:
Prospective evaluation in consecutive patients.

SETTING:
Academic level 1 trauma center.

PATIENTS:
Three-hundred patients with an operatively treated ankle fracture who met the inclusion and exclusion criteria.

INTERVENTION:
Injury ankle radiographs were assigned to a Lauge-Hansen classification. MRI scans were obtained to evaluate the syndesmotic and deltoid ligaments. A Lauge-Hansen classification for each patient was recorded based on intraoperative findings.

MAIN OUTCOME MEASUREMENTS:
Comparisons were made between the predicted ankle ligamentous injuries based on radiographic Lauge-Hansen classifications, preoperative MRI analyses, and intraoperative findings.

RESULTS:
On the basis of the Lauge-Hansen system and injury radiographs, 77% (231/300) were classified as supination external rotation, 13% (40/300) were pronation external rotation, 4% (11/300) were supination adduction, < 1% (1/300) was pronation abduction, and 6% (17/300) were not classifiable. Of the 283 fractures that were classified into Lauge-Hansen classes, 266 (94%) had MRI readings of ligamentous injuries consistent with the Lauge-Hansen predictions. Intraoperative findings also highly correlated with the Lauge-Hansen class of ankle fractures, with nearly complete agreement. Comparing MRI and intraoperative findings revealed discrepancies in 6% (16/283) of ankle fracture classifications.

CONCLUSIONS:
In our large cohort of patients, comparisons between injury radiographs, preoperative MRI, and intraoperative findings suggest that the Lauge-Hansen system is an accurate predictor of ligamentous injuries. The predictions based on the Lauge-Hansen system can be useful for fracture reduction maneuvers and operative planning.

LEVEL OF EVIDENCE:
Diagnostic Level II. See Instructions for Authors for a complete description of levels of evidence.